Arccos
反余弦
??? 情景例句
I'm not quite familiar with the claim and arbitration in international trade.
我對國際貿(mào)易的索賠與仲裁不夠熟悉。
It is one thing to speak much and another to speak pertinently.
話講得多是一回事，講得恰當是另一回事。
New York is built on a group of islands on the east coast of the USA at a point where several rivers flow into the ocean.
紐約市建立在美國東海岸的一群島嶼上，那兒是好幾條河流入海的交匯點。